Individuals infected with HIV-1 often make vigorous anti-viral CD8 cytotoxic T lymphocyte (CTL) responses. The CTL appear to play an important role in reducing the viral load but infection usually persists and eventually worsens. The long-term goal of this project to is facilitate the development of vaccines aimed at generating more effective CD8 CTL responses than occur in the course of natural infection. To this end we will define the maximally effective forms of heat shock fusion protein and DNA vectors as immunogens for eliciting potent primary and memory CD8 cytotoxic T lymphocyte (CTL) responses in a transgenic mouse model with aim of eventually applying related immunogens to the vaccination of nonhuman primates (macaque monkeys?) against SIV infection.